Automatic and semiautomatic telephone exchange system



Feb. -16, 1932'.

e. DEAKIN ET AL 1,845,248

AUTOMATIC AND SEMIAUTOMATIC TELEPHONE EXCHANGE SYSTEM Filed May 13, 1930 625mm 054/0 5., [/94 Ana/wars): a-ca, 5;, [0004/90 FRI/M,

IOMIIYISTRATGQ.

ATTORNEY Patented Feb. 16, 1932 UNITED STATES} PATENT OFFICE GERALD DEAKIN, or New YO K, N. Y., AND mi ro InKowsKY, DECEASED, LATE or PARIS, FRANCE, BY EDOUABD lRUM, ADMINISTRATOR, or PARIS; FRANCE, AS- sIeNoRs T0 INTERNATIONAL. STANDARD nLnc'r rc CORPORATION, or New YORK,

AUTOMATIC AND SEMIAUTOMATIC TELEPHONE EXCHANGE SYSTEM Application filed May 13, i930, Serial110,452,084,-andcin GreateBritain m 14, 1929.

This invention relates to automatic semiautomatic telephone systems and is concerned more particularly with such systems in which two-wire junctions are provided over which inter-exchange connections I are are extended.

It is common to providein such two-wire junctions a transmission bridge from which talking current is fed during conversation. in the direction of the calling and called parties. An object of the presentinvention is the provision of .simple and eflicient means for cutting out the transmission bridge dur ing the setting up of a connection over the 3 junction and for replacing the. bridge. im-

mediately the connection has beencompleted.

Such a provision is particularly necessary in a system of the kind to which the invention is described as applied'in which revertive con-:

trolling impulses are sent over a metallic circuit extending to a register controller.

According to a feature of the inventiona relaygroup associated with a two-wire junc tion comprises a relay which is adapted to be operated immediately the junction is taken into use and which in its operated condition is adapted to cut out a transmission bridge normally inserted in the junction. The transmission bridge remains cut out during the extension of the connection over one or more switching stages but is reinserted on the completion of the connection-in response to the operation of a polarized relay also comprised in said relay group.

According to a further feature in-a tele transmission bridge, means is associatedwith.

said junction for cutting out said transmission bridge when the unction is taken nto use and for reinsertmg said brldge onthecompletion of a connection over the junction, both the operations being brought about re-.

sponsive to signals transmitted from said registering and controllingmechanism.

The invention is described as applied toa systemof the kind described in our co-pending application U. S;'S'er. No- 452,083, and

are identical with circuitsdescribed and illustratedin that'application in which other features jarefclaimed. I

In the accompanying drawings Fig. 1 shows a relay group situated at the incoming end of a two-wire junction, whilst Fig. 2 shows a registergcontroller circuit v in which a wanted number is adapted to berecorded and which, exercises its controlling action through "the medium of revertive impulses sent back from selector switches at the various switching stages as the connection progresses. For .a complete understanding of thepresent invention it has only been thought necessary to include in the present applicationdrawin'gs of the register controller and of the junctionrelay group, since anunderstandingof the operation of the system as a whole can be obtained by reference to the main application. Reference characters id'entical'with those in the main application have; howevenbeen used to .facilitate a clear understanding of-all the circuits shown, so that the circuits not described can be readily followed by reference to the main application. I

When a calling party initiates a call to a distant exchange his lineis connected over first and second line finders to anidle registwo-wire junction suchz as IJ Fig." 1. 'All these operations take place in themanner described in detail in the copending application referred-to and it has not been thought necessary to again describe the ordinary op erations of the system. v

VVhen, as described in the copending application at the end of the first-selection the a wire is connected tobattery in the register cir cuit overcontacts' KrS, Fig. 2,and the 6 wire to earth over contacts K14, winding of relay Pr, contacts E116, a high resistance super visory relay Sbr Fig. 1 which is normally bridged acrossthe junction in series with the low resistance supervisory relay Say" energizes; relay Sm remains unope ratedr Relay S61 closes a circu t via contacts Brl for relay coming group finder. Relay Br feedsholding" ground forward oyer the third wire. Relay Cr. is now-inserted-in series in the a wire'andis shunted by-the resistance; R and one ofthe talking condensers. This relay 0% is polarized and does not operate at this time nor during theizfurth'er settingupi'of' the connec tion which takes place in the manner fully described in "the copendiiig -application under the control of the register circuit.

At the end of a selection or ona premature release when relay Drr, Fig; 2"energizes and brings about the release of the register circuit,

a potential of roppositepolar'it'y is connected to the a wire for a short interval over contacts Gmiii and D1 24 during the relapse of the slow rele'a'sierelayGar. Relay QC?" which always finds a ground; over the start/relay new of the control circuit of a second group of final finder now' responds and unlocks relayAi-Z ,whichflcannot 're-ene'rgize during the sloWfrele-ase period of relay Br. The high re} sistanee' bridge relay S67 now becomes energized to battery and 'earthatthe"callingline-r' COlClc Clr C lllt over a relay and a retard and hold'sY'relayjBrover contacts Br2 fand Sbrl. Relay Br holds over its left-hand non-inductivehigh'res'istanc'e winding in series with'its right-hand winding to economize in current and'to render this relay relativelyquick to release at the, end of conversation. Onthe reply of the calledtparty talking currentisfed:

over a retardand thesupervisory relay S61 causing the response of the low resistance supervisor relay Sar and a supervisory relay in the calling line cord circuit. Relay Sm". holds relay B1". premature release of the register circuit isres leased as described in the co-pending application and'the impulse of opposite polarity, previously referred-to is sent to the incoming.

relay'groupand causes'the response of the re lay Crthereat; On the response of relayoahoweveryno circuitis found for "relay Sb? andthe. relay Br releases and initiates the-re lease of the succeedingswitches.

A'jackEOJ is provided for disablingthe junction.

What is claimed is 1 In "or for an automatic .or semi-automatic telephone system a relay group associated W with a two-wire junction comprising, means forcuttlng out a transmission bridge in said junction during the establishment of a connection over one ormore subsequent switchingstages and a polarized relay which" 1s, adapted to be operated subsequently to bring aboutj the I rein ser-tion of i said trans mission bridge.

2 Aftelephone system in"whicha regis- In the case olia tering and controlling mechanism is employed for controlling the extension of a connection over a two-wire junction which normally includes-atransmission bridge, in which means is associated With'said junction'fo'r cutting out'said'transmission bridge when said junction is taken into use and-for reinserting said bridge on the completion ofa connection over said 1 j unction, both said roperations being brought about responsive to signals tr-ansmitted from said registering and controlling mechanisan;

8. In or for a telephone system a relay gr'o-upior use atthe incoming'encbof a two- Wire junction which normally includes A a transmission bridg said relay "group coinprising relay lwhichis adaptedtobeiopen ated when saidjunction is takeninto use-to cutout said transmission 'bridge' and to in sert inseri'e's with oneofth juncti-en con ductors a further relay which is adapted to respond subsequentlytoa signaiPsent over said fjunction conductor and to cause thereby the reinsertion of said transmission bridge."

Ai'telephone system as claimed inclain'i said junctionistakeninto usesaid relay ;be-

ingfadapted to closea circuit for aiurth'errelay Whichiin its operated'conditi'on cuts out" sai d transmission bridge? and inserts the Wind ing of; a polarized relayin'seri'efs withon'e' of the junction conductorsfi v 5. A telephone. systemas claimed inclaii'n 2 in which said registering and controlling mechanismexercises its controlling action through the medium of re'ver'tive signals sent from switching apparatus c at "the successive switching stages "over" a metallic circuit 'in=l cludingthe conductors of said junction? 6.' Ina telephone-system a two-Wire junc tion, a transmission bridge' normally inserted insaid junction, means for :cutting outfsaid transmission bridge and'substituting a metallic circuit over said unction'during the estab lis'hm'ent ofa connection; and means forre-. inserting said bridge when the connecti'onds completed.

7. In a telephone systemfa two-wire jute tion, 'a transmissionbridgefnormally inserted in said junctiom-mean's for 'cutting'out' saidtransmission bridge duringthe establishment of a connection-over one or more subsequent" automatic switching stages and means for automatically reinseiting said bridge in case of a premature release by the calling party.

8. Ina telephone 'systeim-a two-wire'junction,a metallic circuit including the twota'lking conductors of said junction for control ling the operation of an" automatic switch at the incoming end thereof, and means for iniii) on the completion of a connection thereover.

9. In a telephone system, atwo-wire junction, a transmission bridge normally inserted in said junction, a relay for cutting out said transmission bridge and substituting a metallic path over said junction, means for operating said relay when said junction is taken into use, a further relay which in its operated condition is adaptedto open the circuit of said first relay and means for energizing said further relay at a subsequent stage in the connection.

10. A telephone system comprising a two wire junction having a transmission bridge 7 normally inserted therein, a relay group comprising a relay adapted to be operated immediately said junction is seized to extend a connection, and thereby cut out said bridge, and a polarized relay, Whose operation is effective to restore said bridge, having its winding inserted in series with one conductor of said junction during the setting up of the connection, the said polarized relay being adapted to respond to a reversal of current over said junction conductor whenthe connection is completed or on a premature release by the calling party.

11. In a telephone system comprising a registering and controlling mechanism for controlling the extension of a connection over a two-wire junction which normally includes a transmission bridge, the combination of a relay normally bridged across the conductors of said junction and operative on the completion of a loop circuit over said conductors I when said junction is taken into use, a second relay controlled by said relay and adapted when operated to cut out said transmission bridge and to insert the winding of a polarized relay in series with one of said junction conductors, said polarized relay being responsive to a current reversal initiated in said registering and controlling mechanism on the completion of the connection, and means whereby the operation of said polarized relay causes the deenergization of said second relay whereby the transmission bridge is reinserted.

12. A telephone system as claimed in claim 11 in which the operation of said polarized relay also causes said first mentioned relay to be reconnected in bridge across said junction conductors and means is provided whereby on the reply of the called party the winding of said relay is short-circuited to cause a supervisory signal to be sent over said junction.

In Witness whereof, We hereunto subscribe our names this 27th day of February, 1930, and 3rd day of February, 1930.

GERALD DEAKIN. EDOUARD FRUM,

Administrator of the Estate of Lipa Polin- Y leowslcy, Deceased. 

